1. Field of the Invention
This invention relates to a naturally occurring anthocyanin from `Heavenly Blue` Morning Glory and more is specifically to its use in coloring food products.
2. Description of the Prior Art
It is known that most naturally occurring anthocyanins are highly colored at pH's below 3 but it is also well know that they are virtually colorless in an environment having pH values above 3.0 (Acta Horticulturae 63, 217-223, 1976). It is also known in the art that anothocyanins acylated with caffeic acid are stable in neutral solution (Bot. Mag. Toyko 87, 33-40, 1974, and Phytochemistry 16, 1118-1119, 1977) and that the major anthocyanin in `Heavenly Blue` Morning Glory, peonidin 3-(dicaffeylsophoroside)-5-glucoside, is one of the few natural anthocyanins acylated with caffeic acid (Phytochemistry, ibid.). Other studies concerning the anthocyanin in morning glory and other plants and natural colors from a variety of sources have also been reported (Kumanato, J. Sci. Biol. 12, 41-70, 1975; Food Engineering 49, 66-72, 1977).